Staff from Montana Fish, Wildlife & Parks and partnering organizations recently released 26 bighorn sheep into the Tendoy Mountains as part of a new effort to re-establish a wild sheep herd there.
The sheep — 19 ewes, five rams and two lambs — were captured from Wild Horse Island on Flathead Lake, where sheep numbers have grown past management objectives. Each of the sheep had healthy body conditions when they were successfully released on Feb. 19.
During capture work, FWP staff outfitted the adult and yearling sheep with GPS collars. These collars will provide daily locations of the sheep that will help biologists monitor their movements, habitat use and survival in the Tendoys.
Between 2021 and 2022, biologists hope to release a total of 60 sheep in the Tendoys to establish a self-sustaining bighorn population there.
Bighorn sheep are native to the Tendoy Mountains and many other mountain ranges in southwest Montana. Native American pictographs in the Tendoys and Lima Peaks are evidence of historical sheep presence. By 1940, however, bighorn sheep were gone from the Tendoys, likely due to unrestricted hunting and disease.
In 1985 and 1986, FWP released 53 bighorn sheep into the Tendoys, and the herd grew to include more than 150 animals. In 1993, the herd began experiencing pneumonia-related die-offs and chronically low lamb recruitment.
In 2015, FWP initiated a plan to depopulate the Tendoys herd and restock it. This unique strategy involved removing sheep primarily via hunter harvest. Since then, there has been no evidence of bighorn sheep inhabiting the area, allowing the restocking effort to begin.
Since bighorn sheep were initially reintroduced in the Tendoys in 1985, the potential for commingling with domestic sheep has been reduced significantly. The GPS collars will play an important role as biologists evaluate the restoration effort’s success, identify and respond to potential risks, and gain knowledge that will inform future reintroduction efforts.
Wildlife managers hope to see the herd grow to about 150 sheep. Hunters will continue to play an important role in maintaining the population at relatively low densities to reduce the potential for disease transmission.
Many organizations and agencies contributed to the success of this year’s sheep restoration efforts in the Tendoys. Funding was donated by the National Wild Sheep Foundation, the Montana Wild Sheep Foundation, and the Bass Pro Shops and Cabela’s Outdoor Fund. The project was also supported by the Bureau of Land Management, the Beaverhead-Deerlodge National Forest, sportsmen and private landowners.
“We’re excited to once again have bighorn sheep in the Tendoys,” said FWP’s Dillon-area wildlife biologist Jesse Newby. “We’re grateful to our many partners for their collaboration, financial support and volunteerism.”